General guidance becomes useful when it leads to better evidence. Record the current fuel, annual consumption where available, rooms or zones that struggle, comfort hours, hot-water pattern and any planned building work. A product figure is not a household or business bill forecast: compare options using the same weather, tariffs, demand, temperatures and scope.
Annual heat demand
Running cost starts with how much useful heat and hot water the building needs across the year. Historic fuel use can help, but boiler efficiency, occupancy changes and missing records introduce uncertainty. A design calculation and sensible annual-demand model should be kept beside any cost comparison.
General guidance becomes useful when it leads to better evidence. Record the current fuel, annual consumption where available, rooms or zones that struggle, comfort hours, hot-water pattern and any planned building work. A product figure is not a household or business bill forecast: compare options using the same weather, tariffs, demand, temperatures and scope. Ask the designer to state what has been measured, what remains assumed, who owns the enabling work and how performance will be checked after commissioning.
Seasonal efficiency
A heat pump’s seasonal performance depends on source temperatures, required flow temperatures, cycling, defrost, hot-water production, controls and commissioning. One laboratory coefficient of performance is not a prediction for every hour or every building.
General guidance becomes useful when it leads to better evidence. Record the current fuel, annual consumption where available, rooms or zones that struggle, comfort hours, hot-water pattern and any planned building work. A product figure is not a household or business bill forecast: compare options using the same weather, tariffs, demand, temperatures and scope. Ask the designer to state what has been measured, what remains assumed, who owns the enabling work and how performance will be checked after commissioning.
Tariffs and time
Electricity price, standing charges, time-of-use opportunities and any retained fuel all matter. Commercial buildings may also have capacity, demand or half-hourly considerations. Use current tariff assumptions and show how sensitive the result is to change.
General guidance becomes useful when it leads to better evidence. Record the current fuel, annual consumption where available, rooms or zones that struggle, comfort hours, hot-water pattern and any planned building work. A product figure is not a household or business bill forecast: compare options using the same weather, tariffs, demand, temperatures and scope. Ask the designer to state what has been measured, what remains assumed, who owns the enabling work and how performance will be checked after commissioning.
Operation and handover
Weather compensation, schedules, setbacks, zoning and user expectations change performance. The system should be commissioned, balanced and explained so it is allowed to operate as designed. Keep settings and meter readings for later review.
General guidance becomes useful when it leads to better evidence. Record the current fuel, annual consumption where available, rooms or zones that struggle, comfort hours, hot-water pattern and any planned building work. A product figure is not a household or business bill forecast: compare options using the same weather, tariffs, demand, temperatures and scope. Ask the designer to state what has been measured, what remains assumed, who owns the enabling work and how performance will be checked after commissioning.
